200 



MEMOIRS OF THE XEW YORK BOTAXICAL GARDEX 



EXPLANATION OF CHART 9 



Here are grouped the records for the variety Taft for the different 

 days of observations during the season of 1925. These records are all 

 from obsem-ations made on one tree with, however, frequent check com- 

 parisons on numerous other trees of this variety. As shown there was 

 only one day (^larch 11) when tlie firets of the forenoon were all fully 

 closed before the seconds started to open. There was, however, but one 

 day (Februan^ 25) when the latter were observed to shed pollen for a 

 short time while firsts were still open. 



A few days of unusually warm weather early in the season of bloom 

 brought the periods of opening rather early in the day. Then cooler 

 weather came and the hours of openings were decidedly later in the 

 day, but from then on to later dates there was a steady advance to earlier 

 hours as indicated, with, however, variations from day to day with devi- 

 ations in weather. 



In only one set of flowers was there a noticeable irregularity; the set 

 in the second period of opening on the afternoon of jMarch 3rd remained 

 open over night and shed some pollen early the next forenoon. 



The record shows a mo.st decidedly exclusive opening of the two sets 

 with extremely rare chances for any close-pollination. 



This variety has first -flowers opening in the forenoon. These flowers 

 close about midday and remain closed all afternoon, all night, and all the 

 next forenoon. Thus they open and shed pollen in the afternoon some 

 25 hours after the first closing and apparently some 26 hours after the 

 point of highest receptivity for proper pollination. Self-pollination 

 seems almost impossible in this variety and in othex's with similar flower 

 behavior. It is not surprising that a tree of the Taft variety set very few 

 fruits in the tenting test and that isolated trees and solid blocks of the 

 Taft variety should be repeatedly shy in bearing. 



